TITLE:
Carbon Nanotubes as Nanosensor for Differential Electrolytic Micropotentiometry
AUTHORS:
Abdulaziz N. Amro, Abdalla Mahmud Abulkibash, Muataz Ali Atieh
KEYWORDS:
CNTs, Silver Electrode, Differential Electrolytic Potentiometry
JOURNAL NAME:
American Journal of Analytical Chemistry,
Vol.5 No.13,
September
24,
2014
ABSTRACT: Carbon nanotubes as
nanosensor were synthesized on the surface of the silver electrode using
floating catalyst chemical vapor deposition reactor. Acetylene gas was used as
a carbon source, ferrocene as a source of the iron nanocatalyst and hydrogen as
a carrier and an activate agent. Several runs were performed to find the
optimum conditions that produce sensitive Ag-CNTs electrodes. The electrodes obtained
at each run were characterized by SEM. The optimum conditions that produce
sensitive Ag-CNTs were found to be at a reaction time of 15 minutes, reaction
temperature of 700°C, hydrogen flow rate of
25 ml/min and an acetylene flow rate of 75 ml/min. These optimum conditions
were confirmed from the normal behavior of the resulting Ag-CNTs electrodes in
the titration of 10 μL of chloride using dc differential electrolytic
potentiometry. When conditions that differ from the optimum ones were applied
in the preparation of the Ag-CNTs electrodes, abnormal titration curves were
obtained. The superiority of the Ag-CNTs electrodes was demonstrated by the
successful applications of these electrodes as an indicating system in the
micro titrations of different volumes of cyanide solution with silver nitrate
reach. By applying this technique a volume of 1.2 μL sample of cyanide was
successfully titrated. The normal behavior of the Ag-CNts electrodes was
compared to that of the normal silver electrodes which exhibit an abnormal
behavior.